Coulomb and nuclear breakup of a halo nucleus 11Be

Breakup reactions of the one-neutron halo nucleus 11Be on Pb and C targets at about 70 MeV/u have been investigated by measuring the momentum vectors of the incident 11Be, outgoing 10Be, and neutron in coincidence. The relative energy spectra as well as the angular distributions of the 10Be+n center of mass have been extracted for both targets. For the breakup on Pb target, the selection of forward scattering angles is found to be effective to extract almost purely the first-order E1 Coulomb breakup component, and to exclude the nuclear contribution and higher-order Coulomb breakup components. This angle-selected energy spectrum is thus used to deduce the spectroscopic factor for the 10Be(0+) 2s_1/2 configuration in 11Be which is found to be 0.72+-0.04 with B(E1) up to Ex=4 MeV of 1.05+-0.06 e2fm2. The energy weighted E1 strength up to Ex=4 MeV explains 70+-10% of the cluster sum rule, consistent with the obtained spectroscopic factor. The non-energy weighted sum rule is used to extract the root mean square distance of the halo neutron to be 5.77(16) fm, consistent with previously known values. In the breakup with C target, we have observed the excitations to the known unbound states in 11Be at Ex=1.78 MeV and 3.41 MeV. Angular distributions for these states show the diffraction pattern characteristic of L=2 transitions, resulting in J^pi =(3/2,5/2)+ assignment for these states. We finally find that even for the C target the E1 Coulomb direct breakup mechanism becomes dominant at very forward angles.Comment: 14 pages, 7 figures, accepted for publication on Physical Review

Mineral Chemistry and Reflectance Spectra for the Anorthosite Clast in Lunar Meteorite Dhofar 489 with Reference to Lunar Farside Crust.

第2回極域科学シンポジウム/第34回南極隕石シンポジウム 11月18日（金） 国立国語研究所 2階講

SU(2)-invariant reduction of the 3+1 dimensional Ashtekar's gravity

We consider a space-time with spatial sections isomorphic to the group manifold of SU(2). Triad and connection fluctuations are assumed to be SU(2)-invariant. Thus, they form a finite dimensional phase space. We perform non-perturbative path integral quantization of the model. Contarary to previous claims the path integral measure appeared to be non-singular near configurations admitting additional Killing vectors. In this model we are able to calculate the generating functional of Green functions of the reduced phase space variables exactly.Comment: 12 page